AAON LZ Series, Установка, эксплуатация и обслуживание

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BMS system can access and modify all
necessary points.
Each individual boiler is provided with flow
balancing valves. Flow should be balanced
between the two evaporators by a hydronic
systems balancing professional.
Boiler Sequence of Operations
1. When both the boiler run/stop switch and
the boiler BMS run/stop input (if BMS
communications
are selected) are
switched on, the unit controls will turn on
the boiler building pump and enable the
lead boiler.
2. If variable speed boiler building pump is
selected, the controls will modulate the
boiler to maintain the target difference
between the pumps suction and discharge
pressures. If the minimum (default 5 psi)
differential is not achieved within 60
seconds then the pump will be locked off
and the next pump will start if available.
3. When the lead boiler is enabled it will
modulate itself as well as stage and
modulate any additional boilers to
maintain
the desired hot water
temperature leaving the unit. This
temperature is controlled through the
chiller unit controller and can be reset
through the BMS communications (if
selected). If BMS communications are
not selected, the target temperature can be
reset
based on the ambient air
temperature. The default temperature
target is 135° F with a minimum of 90° F
and a maximum of 180° F.
4. Each boiler will control its own
individual pumps or valves as necessary
as they are staged on and off.
Maintenance
General
Qualified technicians must perform routine
service checks and maintenance. This
includes
reading and recording the
condensing and suction pressures and
checking for normal sub-cooling and
superheat.
Air-cooled chillers and evaporative-
condensed chillers require different
maintenance schedules/procedures. Unit
specific instructions for both types are
included in this manual.
Refrigerant Suction Line Filter
Each refrigerant circuit contains a
replaceable core suction line filter. One
month after start-up , remove the filter
element.
The replaceable core suction filters are
provided with pressure taps and shutoff
valves for isolation when removing the filter.
For safety purposes a service manifold must
be attached prior to filter maintenance.
Prior to filter core service, a service
manifold MUST BE attached to in and
out pressure connections to assure no
pressure
exists during filter
maintenance. Non-compliance could
result in injury or violation of EPA
regulations.
Service gauges MUST BE connected
before operating the isolation valves
for the replaceable core filter.
WARNING
WARNING